griffin



(No Model.) 2 Sheets-Sheet 1.

J., K. GRIFFIN.

METHOD OF REDUCING ORES, m. No. 318,245. Patented May 19, 1885.

(No Model.)

2 Sheets-Sheet 2. J. K. GRIFFIN.

METHOD OF REDUCING-GEES, &c.

No. 318,245. Patented May 19, 1885.

Ill/Ill N, FErERS, Fhno-Ulhognphen wnshmgwn, D. c,

UNITED STATES PATENT OFFICE.

JAMES K. GRIFFIN, OF BROOKLYN, NE\V YORK, ASSIGXOR TO THE GRIFFIN llIANUFAOTUR-ING COMPANY.

' I METHOD OF REDUCING O'RES, 8&0.

SPECIFICATION forming part of Letters Patent No. 318,245, dated MaylQ, 1885.

Application filed August 1-1, 15794. (No model.) i

' To all 2071,0111 it may concern.- \Vithin the shell or also a is a rotating con- Be it known that I, JAMES K. GRIFFIN, a veyer, c, which is fast on ashaft,f. This shaft citizen of the Dominion of Canada, residing in is jonrnalcd in bearings in a tubular shaft or the city of Brooklyn, in the count-y of Kings sleeve, (1, and in a lower step bearing on the 5 and State of New York, have invented eerframe. The sleeved isrigidly connected to the tain new and useful Improvements in Methods shell a and journaled in boxes on the machine of Reducing Ores and other Substances, of frame. A bevel gear-wheel, c, is fast on the which the following is aspecification. sleeve (7, and a bevel gear-wheel, is fast on My invention relates toamethod of reducing the shaftf, so that suitable bevelgears on a 60 to ores and other substances by attrition; and it driving-shaft may mesh with gears c c for roconsists in carrying off the reducedsubstances tating the shell a and conveyer c independby passing a current of air directly upon the en tly of each other. Preferably, the gearing is line of attrition between opposing revolving so arranged that the shell a shall have twice surfaces of the materialto be reduced. the rotative speed of the conveyor 0, and so 6 '15 It further consists in forming and maintainthatthe shell and conveyor rotate simnlta ing aline of attrition between opposing snrneously in opposite directions. facesof the substance to be reduced by passing The rotative speed of the shell and consaid substance through a rotating conveyer veyer, respectively, may be varied to suit the and against an annular wall of the same subrequirements of different classes of material, 70

2o stance firmly eompactedinarotating shelhand and effective results have been attained by then carrying the pulverized substance oft by rotating the shell and convcyer in the same a current of air communicating directly with direction when the speed of the shell considerthe line ofattrition, as willbe hereinafter more ably exceeds that of the conveyer. The confnllydescribed, and pointed outin the claims. veyer e is divided vertically and radially, 75

The object of my invention is to provide a preferably into four passages arranged in opmethod of reducing refractory ores and other posite pairs, two opposite passages, y g, being substances better and more economically than 1 arranged so as to connect with the central pashas heretofore been done. This method may sage, t, which opens into the hopper I), to con be carried out in machines and by devices of duct therefrom the crude substance down to 80 various constructions; but I prefer to use the the out-lets ol' the passages These outlets mechanism illustrated in the accompanying face the inner periphery of the shell (1, and drawings, forming apart of this specification, have, preferably, a rectangular form and a 1 wherein like letters refer to similar parts, and marginal contour conforming horizontally to L in 'whieh the curve of the shell. S5

Figure 1 is avert-ical section of the machine, In the construction of machines for differtaken on the line a m in Fig. 3. v Fig. 2 is a cut substances, the space between the outlets vertical section thereof, taken on the line'g and the inside of the shell may be varied ac- Fig. Fig. 3 is a horizontal section thereof, cording to the quality of the material to'be taken on the lines a Figs. 1 and 2. Fig. dis compacted or consolidated therein, as some 90 40 a plan view of the top of the machine, showsubstances require more space than others for ing the hopper and exhaust-pipe. the formation of a firm annular wall.

The letter a indicates a spheroidal shell or The compartments 7: 7; of the conveyer 0, case made, preferably, of upper and lower which alternate with its passages r are disections bolted together at their peripheral vided horizontally by plates 022, so that the 3 5 edges, and forming a close tight-bottomed respaces under them connect with the passages ceptacle. It is made open at the top and rep p and the spaces above them with the exvolves as closely as may be beneath a caphaust-pipes 0 o, to provide passages around plate or cover, b. This cover is bolted to the the plates at for a current of air, which curinachine-frame, and is provided with openrent of air may be caused by a suction-fan or I00 ings for the passage of the material to and other suitable device. The rings Z Z are emfrom the machine, as hereinafter described. ployed to strengthen and protect the conveyor.

The letters 8 s indicate the upright supports of the machine-frame, which are bolted to its base it 1. These supports sustain the arms a it, upon which are supported the top plate, I), hopper 71 and exhaust-pipes 0 0.

By reference to the operation of the machine I can now explain the distinctive features of my improved method of reduction. The crude substance is supplied from the hopper it, through the opening i, into the passages g of the rotating conveyer e, and discharged therefrom by centrifugal force against the opposite inner surface of the rotating shell a, but without grinding effect until the shell is filled to the edges of the passages Meanwhile the centrifugal force developed by the rotation of the shell packs the material received from the conveyer 0 into an annular solid wall of sut'ficient firmness to resist the masses forced against and ground upon it, the said wall being indicated by dotted lines, as at 5 As the rotation of the shell and conveyer continues the greater solidity of the annular wall, due to the greater rotative velocity of the shell, gives it a resisting power sufficient to pack the material forced against it, so that the firm bodies of material in the shell and conveyer, re spectively, rotating in opposite directions, are solidly ground against each other on a well-defined line of attrition just outside of and off from the periphery of the conveyer and wholly within the material. The greater the excess of rotating speed in the shell over the conveyer the more compact and solid will the respective bodies in the shell and conveyer be. The solid impact and grinding of the material practically excludes the air from the line of attrition, thereby facilitating the reducing process. As the work of reduction progresses a current of air, passed downward through passage 1) and under plate in immediately against the annular wall at its exposed surface between the passages l/ 9, acts as an air-brush, and by a rotating or whirling motion sweeps the reduced material clean from the surface of the annular wall directly in the lineof attrition as fast as the reduction takes place, leaving the clean, sharp, and unclogged surfaces of compact crude material to grind against each other, while the powdered product is carried off by the same current over the plate on upwardly through theexhaust-pipes 0 0 to any suitable settler or reception-chamber. The force of the current of air is adjusted to and determines the grade of fineness in the product-the lighter the draft the finer the product, and vice versa. This is due to the fact that if the current of air is strong it takes up and carries off all the pulverized particles, whether they are coarse or very fine, whereas if the current of air is weak it will not carry off the coarser particles, and allows them to be ground over and over again until they are fine enough to be carried off by the current of air.

I have demonstrated by continued use that with the shell and conveyer rotating in opposite directions at low speed, not exceeding from one hundred and fifty to two hundred revolutions per minute, very hard substances, as quartz and phosphate rock, can by my method be pulverized in satisfactory quantities to the finest or impalpable powder without injury to the machine.

I make no claim herein for the particular construction of the machine by which I have explained my improved method herein de scribed, as I have applied for a patent on the machine in a separate application, Serial No. 159,399, March 19, 1885.

Having thus described my invention, what I claim as new, and desire to secure by Letters Patent, is-- i. In the reduction of ores and other substances by attrition, the herein described method of carrying off the reduced substances, which consists in passing a current of air directly upon the line of attrition between opposing revolving surfaees of the material being reduced, substantially as described.

The herein-described. method of reducing oresor other substances, which consists in forming andmaintaining a line of attrition bet-ween opposing surfaces of the substance to be reduced by passing said substance through a rotating conveyer and against an annular wall of the same substance firmly compacted in a rotating shell, and then carrying the pulverized substance off by a'current of air communicating directly with the line of attrition, substantially as described.

In testimony whercofI affix my signature in presence of two witnesses.

JAMES K. (1 Bl FFIX.

Witnesses:

LYNDON I. Sunni, Jlurns Pnnov GRIFFIN. 

